This invention relates to regenerative rectifier apparatus capable of ac to dc rectification and power regeneration from a dc source to an ac supply.
A regeneration feature is often a requirement in a machine tool drive system in order to achieve rapid response to speed control changes. If a frequency command to the motor of the machine tool is reduced and the motor is not under load, it is not necessary to wait for friction and windage losses to slow the motor down when regeneration is available to convert the inertia of the motor to electrical energy. In some prior art drive systems the regenerated energy is dissipated through a resistor.
An object of the present invention is to provide regenerative capability to an ac supply from an ac to dc to ac adjustable voltage, adjustable frequency ac motor drive system.
Another object of the present invention is to provide regenerative capability to an ac supply from an ac to dc to dc adjustable voltage dc motor drive system or an ac to dc adjustable voltage dc motor drive system.
A further object of the present invention is to provide in an ac to dc rectifier the capability of regeneration of power from a dc source to the ac supply by reversing the direction of current flow from the dc output of the rectifier, rather than by reversing the dc output polarity.